Entity Relationship (ER) Modeling

Question 1

It represents the conceptual database as viewed by the end user.

Answer 1

ERD

Question 2

It is the set of possible values for a given attribute.

Answer 2

Domain

Question 3

The ERM uses identifiers—one or more attributes that uniquely identify each entity instance.

Answer 3

Identifiers (Primary Keys)

Question 4

It is a primary key composed of more than one attribute.

Answer 4

Composite Identifiers

Question 5

It is an attribute that can be further subdivided to
yield additional attributes.

Answer 5

Composite

Question 6

It is an attribute that cannot be subdivided. For example, age, sex, and marital status would be classified as simple attributes.

Answer 6

Simple attribute

Question 7

It is an attribute that can have only a single value.
For example, a person can have only one Social Security number, and a manufactured part can have
only one serial number.

Answer 7

Single-Valued Attributes

Question 8

It is an attribute whose value is calculated (derived) from other attributes.

Answer 8

Derived attribute

Question 9

It is used to describe the relationship classification.

Answer 9

Connectivity

Question 10

It expresses the minimum and maximum number of entity occurrences associated with one occurrence of the related entity.

Answer 10

Cardinality

Question 11

It exists in the database only when it is associated with another related entity occurrence.

Answer 11

Existence Dependence

Question 12

It means that one entity occurrence does not require a corresponding entity occurrence in a particular relationship.

Answer 12

Optional participation

Question 13

It means that one entity occurrence requires a corresponding entity occurrence in a particular relationship

Answer 13

Mandatory participation

Question 14

It indicates the number of entities or participants associated
with a relationship.

Answer 14

Relationship Degree

Question 15

It exists when an association is maintained within a single
entity.

Answer 15

Unary Relationship

Question 16

It exists when two entities are associated.

Answer 16

Binary Relationship

Question 17

It exists when three entities are associated. Although higher degrees exist, they are rare and are not specifically named.

Answer 17

Ternary Relationship

Question 18

It guides you in developing logical structures that minimize data redundancies, thereby minimizing the likelihood that
destructive data anomalies will occur.

Answer 18

Design standards.

Question 19

It means minimal access time, which may be achieved by minimizing the number and complexity of logically desirable
relationships.

Answer 19

Processing speed